Heathkit HW-101 Refurb

How a Club Loaner Rig Becomes New Again.

This seemed like an extensive redo, but was not, because many of the boards went mostly untouched. It began with a redo of the HP-23 power supply with an HP-23RL board from The Heathkit Shop. And it ended with replacement of two of the Carrier Oscillator crystals, which with age had changed too much to adjust with serial or parallel capacitance.

For kits anyway, this was the pinnacle – the tip-top. No one would ever make a 20-vacuum tube transceiver again.

I purchased the rig and power supply for $75 from a W5FC
club sale of some old gear. The radio worked, having been gone through by the venerable OM, Don (W9VE).
However, a few issues cropped up, including an un-nulled carrier and a significant difference in
USB and LSB – USB is very muddy sounding and power output was low; LSB was completely normal and contacts
on 40m were made every time the rig was powered up!
In addition, CW output was almost nil with the CW filter in. Both the USB and CW issues pointed to the
center frequency of those two modes being outside the filter passband. Still, it was quite a buy, since
the HP-23B power supply can be found for well over $75 all the time on eBay.

The front panel was dirty and worn from about 35 years of use and storage.The new panel was found on eBay for about $11 and makes the old boatanchor look new.

The rig has stickers from the Heathkit factory where apparently it had been shipped to correct some
problems. These stickers date the rig’s assembly at before 1972. The rig works well with a Turner mic
(also from the same W5FC sale) and a later, fortunate fined was a brand new Electro-Voice 719 microphone
with the box, instructions, and (blank) registration card for $9.99 on eBay.

I chose to only do invisible or ‘functional’ mods which didn’t significantly alter the radio. But here are a list of Service Bulletins and the most popular (and necessary) Mods.

Replaced most the electronic parts with the HP-23RL board from The Heathkit Shop.

Subsequently found an SB-600 speaker, with an additional HP-23A inside for cheap. This had been
originally built by WB8LOL – now K5LOL, Thomas, who’d built it originally built the unit in Detroit. He,
and the rig, found their way to Texas and via K5BJI (Mike Goidl), I obtained the supply.

Parts Sources

As a result of all the research, I’ve found some superb resources for part. Here are a few.

Current Status

There appear to always be a few items remaining to do, but the HW-101 operates properly now and
I’ve had two contacts so far: first on 20m (WA7ND) and the USB appears to work, but the Electro-Voice
mic connector shorted out temporarily ending that QSO. Secondly, on 80m with KC9MOS and the
ElectroVoice mic cord appeared to be working again for the duration. I’ll continue to be looking
for bad out-of-spec parts that might show up in performance, but the rig is working nicely!

Completed Appearance Improvements

Replaced the front panel with a fresh, clean one.

Replaced the rubber feet – McMaster-Carr 9540K56 is a perfect fit for the HW-101

Replaced some missing cabinet screws.

Completed Functional Mods and Improvements

Improved the power supply with a re-cap via the HP-23RL board, cleaning up some poor assembly and soldering.